Physics Letters B最新文献

{"title":"Two-layered compact star in biquadratic spatial metric with distinct core-shell equations of state","authors":"Shweta Saklany ,&nbsp;Neeraj Pant ,&nbsp;Brajesh Pandey","doi":"10.1016/j.physletb.2025.139572","DOIUrl":"10.1016/j.physletb.2025.139572","url":null,"abstract":"<div><div>We develop a smoothly matched and singularity-free model for a two-layered compact star, comprising an MIT bag model type dense core surrounded by a shell of Bose-Einstein condensate. Using a biquadratic spatial metric as the coherent background, the temporal metric potential for each layer is obtained by solving the Einstein field equations. This approach provides a comprehensive understanding of the pressure-density distribution and thermodynamic behavior within the star, offering critical insights into its stability, mass-radius relationship, and overall physical feasibility. A key finding of this study is the existence of a stable core-shell structure, where the two distinct regions are smoothly connected at the junction <figure><img></figure>. Another distinctive feature is the formation of a uniform flow zone close to core-shell junction, where the tangential sound speed remains nearly constant <span><math><msub><mrow><mi>v</mi></mrow><mrow><mi>t</mi><mi>s</mi><mo>,</mo><mi>c</mi></mrow></msub><mo>(</mo><mi>r</mi><mo>)</mo><mo>≈</mo><mn>0.374</mn></math></span>.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139572"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fermions in a (2+1)-dimensional magnetized spacetime with a cosmological constant: Domain walls and spinning magnetic vortices","authors":"Omar Mustafa ,&nbsp;Abdullah Guvendi","doi":"10.1016/j.physletb.2025.139569","DOIUrl":"10.1016/j.physletb.2025.139569","url":null,"abstract":"<div><div>In this study, we investigate the relativistic dynamics of fermions in a (2+1)-dimensional sector of the Bonnor-Melvin magnetic (BMM) spacetime background, which features a homogeneous magnetic field aligned with the symmetry axis and a nonzero cosmological constant while maintaining Lorentz invariance under boosts along the z-direction. We analyze the (2+1)-dimensional solution in gravity coupled with nonlinear electrodynamics, excluding the presence of a brane, and derive the radial wave equation governing relativistic fermions in this background. By transforming the problem into a one-dimensional Schrödinger-like equation, we obtain exact eigenvalue solutions, demonstrating that the system supports impenetrable magnetic domain walls that confine fermionic states. In the process, it is unavoidable to extend our analysis to massless fermions, where we establish the generality (as a byproduct and a side effect of the current study, so to speak) of our findings and show that the stationary states of Dirac-Weyl fermions can give rise to rotating ring-like modes, supporting the presence of spinning magnetic vortices in, for example, magnetized monolayer Dirac materials.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139569"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accretion of the degenerate Fermi gas onto a Reissner-Nordström black hole","authors":"Ping Li ,&nbsp;Jiang-he Yang ,&nbsp;Siwei Xu","doi":"10.1016/j.physletb.2025.139555","DOIUrl":"10.1016/j.physletb.2025.139555","url":null,"abstract":"<div><div>We extend the Rioseco and Sarbach model into Reissner-Nordström black hole accretes degenerate relativistic Fermi gas. The accretion theory is based on the Boyer-Lindquist coordinates and the Fermi gas follows Fermi-Dirac statistics at infinity. The expressions for the particle current density, the stress energy-momentum tensor, and three accretion rates are derived. We first investigated the impact of Risoseco and Sarbach model on the evolution of a black hole's charge. The results show that both the mass accretion rate and charge accretion rate are proportional to the particle accretion rate. We have also provided analytical results at infinity and numerical results within a finite range for these quantities. Our results indicate that the accretion rate decreases as the charge of the black hole increases, suggesting that our accretion model does not violate the cosmic censorship hypothesis. In this paper, we first point out that the accretion of Vlasov gas behaves as an anisotropic fluid containing two perfect-fluid components. One component represents the isotropic Fermi gas fluid, while the other represents a coordinate-dependent null fluid. When using the Boyer-Lindquist coordinate system, we observed that the contribution from the null fluid persists even at infinity, which led to the radial pressure always smaller than the tangential pressure.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139555"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the ϕ-α interaction via femtoscopic study","authors":"Faisal Etminan","doi":"10.1016/j.physletb.2025.139564","DOIUrl":"10.1016/j.physletb.2025.139564","url":null,"abstract":"<div><div>Very recently the Wood-Saxon (WS) type interaction in the single-folding potential (SFP) approach are constructed to simulate the <span><math><mi>ϕ</mi><mtext>-</mtext><mi>α</mi></math></span> potentials. One set of the <span><math><mi>ϕ</mi><mtext>-</mtext><mi>α</mi></math></span> potentials are based on the first principle HAL QCD <span><math><mi>ϕ</mi><mtext>-</mtext><mi>N</mi></math></span> interactions in <span><math><mmultiscripts><mrow><mtext>S</mtext></mrow><mrow><mn>3</mn><mo>/</mo><mn>2</mn></mrow><none></none><mprescripts></mprescripts><none></none><mrow><mn>4</mn></mrow></mmultiscripts></math></span> channel, and in another set, the <em>ϕ</em>-meson nucleus potentials were calculated by employing the quark-meson coupling (QMC) model. By utilizing these two sets of <span><math><mi>ϕ</mi><mtext>-</mtext><mi>α</mi></math></span> potentials, the two-particle momentum correlation of <span><math><mi>ϕ</mi><mtext>-</mtext><mi>α</mi></math></span> in high-energy heavy ion collisions is explored. The numerical results show that the correlation functions at small source size (high density nuclear medium) depend on the employed potential model. Also, the correlation functions are obtained within the Lednicky-Lyuboshits (LL) formalism. For small source size, it is found that, the LL formula returns significantly different values due to the large interaction range of the <span><math><mi>ϕ</mi><mtext>-</mtext><mi>α</mi></math></span> potential.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139564"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Searching for the dark photon at the Future Circular Lepton Collider","authors":"X.G. Wang,&nbsp;A.W. Thomas","doi":"10.1016/j.physletb.2025.139573","DOIUrl":"10.1016/j.physletb.2025.139573","url":null,"abstract":"<div><div>In the context of future electroweak precision measurements at the Future Circular Lepton Collider (FCC-ee), we consider recent proposals aimed at finding signatures of physics beyond the Standard Model. In particular, we focus on recent novel suggestions for very precise direct measurements of <span><math><msub><mrow><mi>α</mi></mrow><mrow><mi>em</mi></mrow></msub><mo>(</mo><msubsup><mrow><mi>M</mi></mrow><mrow><mi>Z</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mo>)</mo></math></span>. It is shown that at a level of precision of order <span><math><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>5</mn></mrow></msup></math></span>, the effects of a dark photon may be very significant.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139573"},"PeriodicalIF":4.3,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dominance of gluonic scale anomaly in confining pressure inside nucleon and D-term","authors":"Daisuke Fujii ,&nbsp;Mamiya Kawaguchi ,&nbsp;Mitsuru Tanaka","doi":"10.1016/j.physletb.2025.139559","DOIUrl":"10.1016/j.physletb.2025.139559","url":null,"abstract":"<div><div>We explore the confining pressure inside the nucleon and the related gravitational form factor referred to as the D-term, using the skyrmion approach based on the scale-invariant chiral perturbation theory, where the skyrmion is described as the nucleon and a scalar meson couples to the scale anomaly through the low energy theorem. Within this model framework, the current quark mass and gluonic quantum contributions to the scale anomaly can be described by the pion and scalar meson masses, respectively, through matching with the underlying QCD. By considering the decomposition of the energy momentum tensor of nucleon, we examine the role of the scale anomaly contributions in the pressure inside the nucleon. As a result, the gluonic scale anomaly is found to dominate the confining pressure. Compared to the result based on the conventional chiral perturbation theory in the chiral limit, our result for the total pressure is capable of qualitatively improving the alignment with lattice QCD observations. Moreover, the pressure from the gluonic scale anomaly is widely distributed in position space, leading to its substantial contribution to the D-term.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139559"},"PeriodicalIF":4.3,"publicationDate":"2025-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental impact of jet fragmentation reference frames at particle colliders","authors":"Lawrence Lee,&nbsp;Charles Bell,&nbsp;John Lawless,&nbsp;Cordney Nash,&nbsp;Emery Nibigira","doi":"10.1016/j.physletb.2025.139561","DOIUrl":"10.1016/j.physletb.2025.139561","url":null,"abstract":"<div><div>In collider physics, the properties of hadronic jets are often measured as a function of their lab-frame momenta. However, jet fragmentation must occur in a particular rest frame defined by all color-connected particles. Since this frame may not be the lab frame, the fragmentation of a jet depends on the properties of its sibling objects. This non-factorizability of jets has consequences for experimental jet techniques such as jet tagging, boosted boson measurements, and searches for physics Beyond the Standard Model. In this paper, we will describe the effect and show its impact as predicted by simulation.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139561"},"PeriodicalIF":4.3,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing Λ potential via its v2 flow in hypernuclei-induced reaction","authors":"Gao-Chan Yong","doi":"10.1016/j.physletb.2025.139549","DOIUrl":"10.1016/j.physletb.2025.139549","url":null,"abstract":"<div><div>The hyperon potential, particularly its behavior at high densities, is crucial for resolving the “hyperon puzzle” in neutron stars and for advancing our understanding of the strong interactions between strange and non-strange particles in high baryon density environments. Using the hadronic transport model AMPT-HC, hypernucleus-nucleus collision is studied. It is found that at beam energies below the threshold for hyperon production, the hyperon elliptic flow exhibits noticeable asymmetry between the positive and negative rapidity regions and is sensitive to the strength of the hyperon potential, especially in the large negative rapidity region. One can extract the hyperon potential approximately twice the saturation density based on the hyperon elliptic flow in the negative rapidity region, and the hyperon potential around the saturation density based on the hyperon elliptic flow in the positive rapidity region.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139549"},"PeriodicalIF":4.3,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electromagnetic leptogenesis with light-heavy sterile neutrinos","authors":"Debasish Borah ,&nbsp;Arnab Dasgupta","doi":"10.1016/j.physletb.2025.139557","DOIUrl":"10.1016/j.physletb.2025.139557","url":null,"abstract":"<div><div>We propose a novel leptogenesis scenario utilising the two-body decay of heavy right handed neutrino (RHN) via the electromagnetic dipole operator. While the requirement of the standard model (SM) gauge invariance requires such dipole operator only at dimension-6 forcing the generation of non-zero CP asymmetry from three-body decay with two-loop corrections, we write down dimension-5 dipole operators involving heavy RHN <span><math><msub><mrow><mi>N</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> and its lighter counterpart <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span>. This allows the generation of lepton asymmetry in <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> from two-body decay of heavy RHN which later gets transferred to left handed leptons via sizeable Yukawa coupling with a neutrinophilic Higgs doublet. The asymmetry in left handed leptons is then converted to baryon asymmetry via electroweak sphalerons. The lepton number violation by heavy RHN also induces a one-loop Majorana mass of <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> rendering the light neutrinos to be Majorana fermions. While smallness of the Majorana mass of <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> prevents additional sources or washout of lepton asymmetry, it also constrains the scale of leptogenesis. Sub-GeV sterile neutrinos, depending upon their masses come with interesting implications for low energy experiments, neutrino oscillation, warm dark matter as well as effective relativistic degrees of freedom. Additionally, heavy RHN can lead to observable monochromatic photon signatures at terrestrial experiments.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139557"},"PeriodicalIF":4.3,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amelino-Camelia DSR effects on charged Dirac oscillators: Modulated spinning magnetic vortices","authors":"Abdullah Guvendi ,&nbsp;Omar Mustafa ,&nbsp;Nosratollah Jafari","doi":"10.1016/j.physletb.2025.139547","DOIUrl":"10.1016/j.physletb.2025.139547","url":null,"abstract":"<div><div>This work explores the two-dimensional Dirac oscillator (DO) within the framework of Amelino-Camelia doubly special relativity (DSR), employing a modified Dirac equation that preserves the first-order nature of the relativistic wave equation. By introducing non-minimal couplings, the system provides an exact analytical solution in terms of confluent hypergeometric functions, along with closed-form expressions for the energy spectrum (indulging a Landau-like signature along with accidental spin-degeneracies)-. In the low-energy limit, the results reproduce the well-known two-dimensional Dirac oscillator spectrum, and in the nonrelativistic regime, the results reduce the Schrödinger oscillator spectrum. First-order corrections in this DSR model introduce a mass-splitting term proportional to <span><math><mo>±</mo><msub><mrow><mi>E</mi></mrow><mrow><mo>∘</mo></mrow></msub><mo>/</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>p</mi></mrow></msub></math></span>, where <span><math><msub><mrow><mi>E</mi></mrow><mrow><mo>∘</mo></mrow></msub><mo>=</mo><mi>m</mi><msup><mrow><mi>c</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> is the rest energy and <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>p</mi></mrow></msub></math></span> is the Planck energy. These corrections preserve the symmetry between the energies of particles and antiparticles around zero energy, but induce a shift in the energy levels that becomes more significant for higher excited states (<span><math><mi>n</mi><mo>&gt;</mo><mn>0</mn></math></span>). By mapping the system to a DSR-deformed charged Dirac oscillator in the presence of an out-of-plane uniform magnetic field, we show that the leading-order Planck-scale corrections vanish at a critical magnetic field <span><math><msubsup><mrow><mi>B</mi></mrow><mrow><mn>0</mn></mrow><mrow><mi>c</mi></mrow></msubsup></math></span>, and as the magnetic field approaches this critical value, the relativistic energy levels approach <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>n</mi><mo>,</mo><mo>±</mo></mrow></msub><mo>=</mo><mo>±</mo><msub><mrow><mi>E</mi></mrow><mrow><mo>∘</mo></mrow></msub></math></span>. Finally, we identify a previously undetermined feature in two-dimensional charged Dirac oscillator systems in a magnetic field, revealing that the corresponding modes manifest as spinning magnetic vortices.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"866 ","pages":"Article 139547"},"PeriodicalIF":4.3,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143935599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}